The goal of this study was to validate the suitability of a novel rotational hydroelastic actuator (rHEA) for use in our new rehabilitation exoskeleton for the upper limbs, the Limpact. The rHEA consists of a rotational hydraulic actuator and a custom-designed symmetric torsion spring in a series-elastic configuration. For rehabilitation therapy and impairment quantification, both compliant impedance control and stiff admittance control modes are possible. In the validation experiments, the torque bandwidth of the rHEA was limited to 18 Hz for a desired 20 N??m reference signal (multisine, constant spectrum) due the transport delays in the long flexible tubes between the valve and cylinder. These transport delays also required changes to existing theoretical models to better fit the models on the measured frequency response functions. The (theoretical) measurable torque resolution was better than 0.01 N ??m and the (validated) delivered torque resolution below 1 N?? m. After the validation experiments, further iterative improvements resulted in a spring design capable of a maximum output torque of 50 N??m with an intrinsic stiffness of 150 N?? m/rad and a slightly higher bandwidth. With the design locked, the maximum measurable isometric torque is 100 N ??m. In conclusion, the rHEA is suitable for upper limb rehabilitation therapy as it matches the desired performance.

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Human-robot control interfaces have received increased attention during the past decades. With the introduction of robots in everyday life, especially in providing services to people with special needs (i.e., elderly, people with impairments, or people with disabilities), there is a strong necessity for simple and natural control interfaces. In this paper, electromyographic (EMG) signals from muscles of the human upper limb are used as the control interface between the user and a robot arm. EMG signals are recorded using surface EMG electrodes placed on the user’s skin, making the user’s upper limb free of bulky interface sensors or machinery usually found in conventional human-controlled systems. The proposed interface allows the user to control in real time an anthropomorphic robot arm in 3-D space, using upper limb motion estimates based only on EMG recordings. Moreover, the proposed interface is robust to EMG changes with respect to time, mainly caused by muscle fatigue or adjustments of contraction level. The efficiency of the method is assessed through real-time experiments, including random arm motions in the 3-D space with variable hand speed profiles.

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На основе уравнений Лагранжа-Максвелла разработан метод решения задачи оп-тимального управления манипуляторами с последовательной и параллельной структурами, рассматриваемыми как элек-тромеханические системы. Метод позволяет без введения дополнительных сил, изменением лишь напряжений в элек-троприводах, спланировать требуемые оптимальные движения механизмов, что существенно упрощает системы их управления.

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Предлагается распространение составленного на основе обобщeнного метода Ньютона-Эйлера алгоритма динамического анализа упругих манипуляторов на случай упругих древовидных механи-ческих систем, свободных от внешних ограничений. Оснащ¸нная расч¸тная схема численного решения смешанной задачи динамики сохраняет в итоге все преимущества, достигнутые ранее при построении отправного алгоритма.

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To describe the ARAMIS (Automatic Recovery Arm Motility Integrated System) project, a concept robot applicable in the neuro-rehabili-tation of the paretic upper limb after stroke. Methods, results and conclusion: The rationale and engineering of a state-of-the-art, hardware/software integrated robot system, its mechanics, ergonomics, electric/electronics features providing control, safety and suitability of use are described. An ARAMIS prototype has been built and is now available for clinical tests. It allows the therapist to design neuro-rehabilitative (synchronous or asynchronous) training protocols in which sample exercises are generated by a single exoskeleton (operated by the patient’s unaffected arm or by the therapist’s arm) and mirrored in real-time or offline by the exoskele-ton supporting the paretic arm.

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